Radiation therapy is a widely used primary treatment for multiple malignancies. However, physical dose measurement is not an effective approach as the biological response of different patients or even different types of cancers are very different for the same physical dose. Moreover, diseased tissue and normal organ radiation sensitivities also vary. Existing medical devices (physical dosimeters) do not satisfy all the metrics for assessing biological response to radiation therapy, especially in a point-of-care manner. IFOS and Stanford University are developing a rapid, portable, easy-to-use and quantitative dose measurement method ? comprising a portable handheld sensor and a novel nanoprobe for rapid, real-time in-situ imaging of cancerous tissue. The probe is designed to detect Reactive Oxygen and Nitrogen Species (RONS) generated due to radiation and charge particle therapy. The innovation will provide greatly enhanced imaging capabilities to oncologists in radiation treatment monitoring.